Stat 281 Chapter 7 F..
... Sample Size for Estimating µ, σ Unknown • If σ is unknown, the confidence interval will be calculated using the t distribution, unless n is very large. • But the degrees of freedom depend on n, which we don’t know. • The calculation also depends on s, which we don’t know until after sampling. • We ...
... Sample Size for Estimating µ, σ Unknown • If σ is unknown, the confidence interval will be calculated using the t distribution, unless n is very large. • But the degrees of freedom depend on n, which we don’t know. • The calculation also depends on s, which we don’t know until after sampling. • We ...
See 8.5 Transformations
... 1) Use a different distribution. For example, Weibull distributions are often used to model lifetimes of machines. 2) There are "nonparametric methods" that don't rely on any assumption about the underlying distribution. These methods sacrifice some power. When a distribution can be used, you are be ...
... 1) Use a different distribution. For example, Weibull distributions are often used to model lifetimes of machines. 2) There are "nonparametric methods" that don't rely on any assumption about the underlying distribution. These methods sacrifice some power. When a distribution can be used, you are be ...
normalMarch2006
... We assume here that the population may be modelled using a normal distribution with unknown mean but known variance 2 For example, suppose one wants to investigate IQ of students at StAndrews. As you cannot study the whole population, you need to measure the IQ’s of a random sample of students. I ...
... We assume here that the population may be modelled using a normal distribution with unknown mean but known variance 2 For example, suppose one wants to investigate IQ of students at StAndrews. As you cannot study the whole population, you need to measure the IQ’s of a random sample of students. I ...
155S6.5_3 The Central Limit Theorem
... male heads when designing motorcycle helmets. Men have head breadths that are normally distributed with a mean of 6.0 in. and a standard deviation of 1.0 in. (based on anthropometric survey data from Gordon, Churchill, et al.). a. If one male is randomly selected, find the probability that his he ...
... male heads when designing motorcycle helmets. Men have head breadths that are normally distributed with a mean of 6.0 in. and a standard deviation of 1.0 in. (based on anthropometric survey data from Gordon, Churchill, et al.). a. If one male is randomly selected, find the probability that his he ...
